Program and/or methods used for detection of leakage of spills from plant systems, structures, and components that have a potential for an inadvertent release of radioactivity from plant operations into groundwater:

Permanent outdoor radioactive water storage tanks at MNGP (condensate water) are located within a basin designed to contain leakage. Leakage from the tanks would be detected either visually or during routine sampling and analysis, which is preformed prior to periodic removal of accumulated precipitation.

The MNGP spent fuel pool has a leak detection system that includes a skimmer surge tank low level alarm, a fuel pool low level alarm, and an inspection of the fuel pool liner drains once per shift.

Engineers perform periodic walk downs of the systems for which they are responsible. These walkdowns include the requirement to identify and report leaks and spills. Leaks and spills are addressed through any of the following: decontamination, notifying supervision for assistance, writing a work request or initiating a Corrective Action Report.

Operations personnel conduct shiftly walkdowns of plant systems and are required to identify and report leaks and spills. Leaks and spills are addressed through ay of the following: decontamination, notifying supervision for assistance, writing a work request or initiating a Corrective Action Report.

The site corrective action program is used for reporting and trending leaks and spills. The process facilitates anonymous reporting.

The Radiological Environmental Monitoring Program (REMP) includes periodic sampling and analysis of onsite and offsite groundwater wells.

Program and methods for monitoring onsite groundwater for the presence of radioactivity released from plant operations:

MNGP has one onsite groundwater monitoring well, which is sampled as part of the REMP. This well is one of several that supply water for employee consumption.

In addition, MNGP samples two offsite groundwater wells (one residential and one public) as part of the REMP.

The wells are sampled quarterly and analyzed for gamma-emitting radionuclides and tritium.